Electric heating device



Aug. 11, 1942. A. c. WILCOX ELECTRIC HEATING DEVICE Filed April 3, 19413 Sheets-Sheet l awe/whorl AMe/fi 6. 7751001 Aug. 11, 1942. A. c. WILCOXELECTRIC HEATING DEVICE Filed April 3, 1941 3 Sheets-Sheet 2 Aug. 11,1942. A. c. WiLCOX 2,292,854

ELECTRIC HEATING DEVICE Filed April 5, 1941 3 Sheets-Sheet 3 PatentedAug. 11, 1942 UNITED STATES PATENT OFFICE ELECTRIC HEATING DEVICE AlbertC. Wilcox, Chicago, Ill.

Application April 3, 1941, Serial No. 386,621

2 Claims.

The invention relates to an electric heating device and moreparticularly to a heating unit adapted to be detachably connected to theoutside of a utensil.

Although the improved heating unit is adapted for connection to any typeof utensil regardless of whether the same is formed of glass, porcelain,metal, or other material, it is especially adapted for attachment to theoutside of the lower coffee pot or container of a drip or vacuum coffeemaker so as to maintain the coffee at the proper temperature forserving.

The object of the improvement is to provide an electric heating devicein the form of a sealed unit arranged to be detachably connected to theoutside of a utensil.

Another object is to provide a heating unit of this character in theform of a split ring or band arranged to be located around the outsideof a utensil and clamped thereon.

Still another object of the invention is to provide a heating unit ofthis character in which the detachable band heating unit is carried bythe handle of the utensil.

The above objects together with others which will be apparent from thedrawings and following description, or which may be referred to, may beattained by constructing the improved heating unit in the mannerillustrated in the accompanying drawings in which Figure 1 is a sideelevation of the lower coffee pot or container of a drip or vacuumcoffee maker showing the improved electric heating unit located aroundthe lower portion thereof in the form of a split ring clamped within anexternal groove in the coffee pot;

Fig. 2, an expanded perspective view of the band heating unit shown inFig, 1;

Fig. 3, an enlarged transverse sectional view through the heating unit;

Fig. 4, a detail elevation of a portion of the heating element locatedwithin the improved heating unit;

Fig. 5, a side elevation of a coffee pot showing a modified form of theheating unit;

Fig. 6, a detached perspective view of the heating unit shown in Fig. 5;

Fig. 7, a rear elevation of a glass coffee container with a band or ringheating unit encased in a circular tube;

Fig. 8, a detached plan section of the heating unit shown in Fig. 7;

Fig. 9, a transverse sectional view through the heating unit shown inFigs. 7 and 8;

showing the heating unit attached to the handle; Fig. 11, a detachedperspective view of the handle and heating unit shown in Fig. 10;

Fig. 12, a fragmentary elevation of a glass coffee container showing ahigh and low stage band heating unit applied thereto.

Fig. 13, a side elevation of a coffee container such as shown in FigureI mounted in a metal cradle which supports the coffee pot raised abovethe surface of the table and permits of pouring the coffee therefromwithout removing the pot from the cradle;

Fig. 14, a detached perspective view of thecradle shown in Fig. 13;

Fig. 15, shows another form of cradle with coffee pot mounted therein;

Fig. 16, a plan view of the pivoted ring forming part of the cradleshown in Fig. 15;

Fig. 17, a sectional elevation of a utensil with a different type ofheating unit band extending diametricall through a groove in the bottomwall of the utensil; and

Fig, 18, a section taken as on the line Ill-48, Fig, 17.

Similar numerals refer to throughout the several views.

Referring first to the form of the invention illustrated in Figs. 1 to4, inclusive, a coffee pot or lower coffee container of a drip coffeemaker, formed of porcelain or the like, is indicated generally at 20 andprovided with the usual pouring spout 2| and handle 22.

A circumferential groove 23 is formed around the pot 20 near the bottomthereof to receive the improved heating unit which is in the form of asplit ring or band indicated generally at 24.

This heating unit as well as the other modifications shown in thedrawings and described hereinafter is a sealed unit so that no water,moisture, or the like will injure the same.

As shown in Figs. 2, 3, and 4, the improved band heating unit includes ahousing formed of a metal strip 25 of substantially channel form havingthe upper and lower angular flanges 26 terminating at their ends in thenarrow angular flanges 21 directed toward each other and swedged overthe upper and lower edges of the metal strip 28 which closes the openinner side of the circular housing thus formed, enclosing the heatingelement therein.

The heating element is preferably of the form best shown in Figs. 3 and4 and comprises a strip of mica 29 having spaced notches 3D in its upperand lower edges, a ribbon 3| of suitable heat similar parts Fig. 10, aside elevation of a cofiee container resisting metal being wound uponthis mica strip and through the notches 30 thereof and connected at itsends to the plug-in points 32 which extend outward from opposite ends ofthe split band.

Strips 33 of mica or the like are located upon each side of the heatingelement thus formed to insulate the same from the metal shell or housmg.

The band heating unit, as shown in Fig. 2, is placed around the lowerportion of the pot 20 within the groove 23 and the insulation terminalblock 34 is positioned to connect the ends of the band, the plug-inpoints 32 being received through the spaced openings 35 in said terminalblock and nuts 36 applied to the threaded portions of the plug-in pointsto clamp the band heating unit in position upon the coffee pot.

It should be understood that the improved heating unit to which theinvention pertains is designed to be of low wattage type so as tofurnish only suflicient heat to maintain the coffee at the desiredtemperature for serving.

In use it will be seen that an electric cord of usual construction maybe plugged upon the points 32 operating the improved band heating unitto maintain the coffee in the pot at the desired temperature for servinguntil the coffee has been poured from the pot.

In Figs. 5 and 6 is shown a modification of the heating unit applied toa coifee pot or container a which may be of metal or the like providedwith a spout 2 la and handle 22a and having a circumferential groove239. near its lower end.

The band heating unit indicated generally at 249 may be formed in themanner above described excepting that it does not form a complete ring,but as shown may be only slightly more than semicircular in form. y

The plug-in points 329. and insulation terminal block 345 may beattached to the central portion of the band heating unit instead of tothe ends thereof as shown in Fig. 2.

Thus as shown in Fig. 5 the band heating unit will extend only partiallyaround the circumference of the utensil upon which it is to be used.

This type of the band heating unit is adapted to be attached by means ofthe arcuate spring clip 31 connected at one end to one end of the unit243 and having a key hole slot 38 at its other end adapted to bereceived over the headed stud 39 carried by the other end of the unit243,.

A curved portion 40 is formed at the center of the spring clip 3!adapted to be pressed inward toward the pot to sufiiciently elongate thespring clip to permit the enlarged portion of the key hole slot 38 to bereceived over the head of the stud 39.

When pressure of this curved portion 40 is released the free end of thespring clip 31 will snap into place as shown in Fig. 5 and the addedtension of the curved portion 40 will hold the band heating unit rigidlyin place within the groove 23;. of the pot.

In Figs. 7, 8, and 9 is shown another modification of the band heatingunit in which the same may be of substantially circular cross sectionalshape instead of fiat as shown in the previous views.

This form of the invention is shown applied to a lower cofiee containerof glass or the like indicated generally at 20b and provided with ahandle 22b, a circumferential groove 23!) being formed around the lowerportion of the cofiee container to receive the heating unit indicatedgenerally at 24b.

This heating unit is of split ring construction and is housed within atubular metal shell or casing 4 I The heating element is in the form ofa ribbon 42 wound upon a core 43 of asbestos or the like and surroundedby an insulation covering 44 of asbestos or the like to insulate theheating element from the metal shell or casing 4|.

The ends of the band heating unit ar outturned as shown at 45 andprovided with the plug-in points 32b.

The insulation terminal block 34b is provided with suitable openings 46to receive the outturned ends 45 of the unit, these openings beingreduced as at 41 to receive the plug-in points 32.

The assembly is fastened together around the utensil as by means of thenuts 36b received upon the threaded portions of the plug-in points.

In Figs. 10 and 11 is shown another modification of the invention inwhich the band heating unit may be mounted upon the handle of theutensil so as to be attached to or removed from the utensil by means ofthe handle.

This form of the invention is shown applied to a lower container or pot200 which may be formed of glass or the like and provided near its lowerend with a circumferential groove 230.

The handle 22:: may be formed of Bakelite or other insulation materialand is connected to the upper portion of the utensil in usual andwell-known manner as by a metal ring 48, the outturned ends 49 of whichmay be detachably connected to the upper end of the handle 22:: as byscrews 50.

A terminal block 340 may be formed integrally with the lower end of thehandle 22c and the heating unit 24c, which may be formed in the mannerabove described, is substantially semicircular and provided with theplug-in points 320 embedded in and extending through the terminal block34c so as to attach the heating unit to the handle.

As shown in Fig. 10 when the handle 22a is attached to the utensil thesemi-circular heating unit 240 will be received in the circumferentialgroove 230 at the lower end portion of the utensil.

In Fig. 12 is shown a coffee container or the like indicated generallyat 20d in which the band heating element 24d may be of any form abovedescribed and located around the groove 23d at the lower portion of theutensil.

This form of the invention is especially adapted for vacuum coffeemakers and is designed to give either high or low heat for the purposeof making the coifee in the utensil and later maintaining the coffee atthe desired temperature for serving.

For this purpose three plug-in points indicated at 22', 22", and 22 areprovided upon the heating unit.

By plugging in the points 22' and 22" the heating unit may be operatedat high temperature for making the cofiee; by then plugging in thepoints 22" and 22" the heating unit may be operated at a lowertemperature for maintaining the cofiee at the desired temperature forserving.

In Figs. 13 and 14 is shown means for supporting a coiTee pot, such asillustrated in Figure l,

This cradle may comprise the two upright side members 52 each having anotch 53 at its upper end to receive the projections or trunnions 54formed upon opposite sides of the pct 20 at a point slightly forward ofthe vertical center thereof.

The lower portions of the side members 52 of the cradle may be coveredwith tubes 55 of rubber or the like to prevent marring the surface ofthe table.

The side members 52 of the cradle are connected together by means of thebars 56 and 51, the rear bar 51 being in position to be engaged by thebottom of the pct 20 to support the pot in vertical position.

When it is desired to pour coffee from the pot it may be tilted to thebroken line position shown in Fig. 13 without lifting it from thecradle.

Another form of the cradle is illustrated in Figs. and 16; the cradleindicated generally at 58 may be formed of sheet metal and a pivotedsupporting ring 59 is mounted slightly off center in the upper endportion of the cradle as by means of the pins 60 located slightlyforward of the center of the ring 59 and journaled in suitable apertures5| in the upper end of the cradle.

The coffee pot has an enlarged shoulder 20 adapted to rest upon the ring59 and this ring has the recessed rear portion 62 through which theplug-in points 32 may pass when the coffee pot is in position in thecradle.

An internal lug 63 may be formed upon one side of the cradle to engageunder the ring 59 so as to normally support the coffee potin verticalposition.

Another form of the invention is shown in Figs. 17 and 18 in which thecoffee container or other utensil 20 has a diametric groove 54 formed inits bottom wall and a circumferential groove 65 near its lower end.

The band heater indicated generally at 24 may be formed in the mannershown in Fig. 3, but is substantially flat excepting for the upwardlycurved rear end 24:.

The terminal block 34. and plug-in points 32 may be secured to this endof the heating unit and a knob 66 is mounted upon the inner side of theunit to engage in the circumferential groove 55 of the utensil.

An upwardly curved spring clip 61 is connected to the other end of theheating unit and provided with a knob 88 to engage in the peripheralgroove 65.

With this construction the band heating unit may be easily and quicklyattached to or detached from the utensil.

Although the improved heating unit is especially adapted for use uponcoffee pots or the lower containers of drip or vacuum coffee makers, itshould be understood that it may be applied to any form of utensil inthe manner above described, for maintaining the contents thereof at anydesired temperature.

Without in any way changing the construction of the invention asillustrated and described the improved heating unit may thus be appliedto casseroles, serving dishes, nursing bottles, or any type of utensilused by the housewife or hotels, restaurants or the like for servingfoods, liquids, etc., and keeping them at proper serving temperatureuntil used.

I claim:

1. In combination with a utensil having a diametric groove in theexterior of its bottom wall, the side walls of the utensil beingrecessed at opposite ends of said groove; an electric heating unit inthe form of an elongated straight band arranged to fit within saidgroove, and means at the ends of said band for frictional engagementwith the recesses in the side walls of the utensil for detachablymounting said heating unit in said groove.

2. In combination with a utensil having a diametric groove in theexterior of its bottom wall and a circumferential groove near its lowerend, an electric heating unit in the form of an elongated band arrangedto fit within said diametric groove, one end of said heating unit beingupturned, a ball upon said upturned end arranged to fit in saidcircumferential groove, and an upturned spring member at the other endof said heating unit provided with a ball arranged to fit in saidcircumferential groove for detachably mounting said heating unit in saiddiametric groove.

ALBERT C. WILCOX.

